Electrical heating utensil



E. J. ROHNE ELECTRICAL HEATING-UTENSIL 2 Sheets-Sheet l Filed June 21, 1926 QZ/i5 VZW Feb. '12, 1929. ,7o2,os9

E. J. RHNE ELECTRICAL HEATING UTENSIL Filed June 21, 1926 2 Sheets-Sheet 2 f 29 20 .e2-Q f ly /g Y J2 3423 l *ll [2 25 25 Mp4/Mv@ i many different uses but especially adapted Patented Feb. 12, 1929. l

PATENT OFFICE.

' EVAN iT. BORNE, CF MINNEAIVOLIS, MINNESOTA.

ELECTRICAL HEATING UTENSIL.

applicati@ med :une 21, 192e. serm No. 117,378.

My present invention provides lan improved electrical heating utensil adapted for for use in cooking vegetables, meats and other edibles, or for boiling or heating liquids; and, generally stated, the invention consists of the novel devices, combinations .of devices, and arrangement of parts hereinafter described and defined in the claims.

rlhe improvementis directed particularly to an improved structure or arrangement which renders assembling of the various elements of the device an easy matter, and access to the various electrical connectionsconvenient.

In the accompanying drawings, which illustrate the invention, like characters indicate like parts throughoutthe several views.

Referring to the drawings:

Fig. 1 is a bottom plan view of the heating utensil;

Fig. 2 is a vertical section taken on the line 2-2 of Fig. 1;

Fig. 3 is an enlarged fragmentary section taken on the line 3-3 of Fig. l;

Fig. 4t is a fragmentary view showing a portion of the bottom of the inner pot, the same being turned upside down; and

Fig. 5 is a diagrammatic view illustrat-ing the heating circuits.

The heater comprises two main elements, to

wit: an outer shell 6 and an inner shell or potl 7 the latter of which is spaced within the former and is provided with a flaring'lid seat 8 terminated in a downturned annular flange 9 that telescopes tightlyover the upper edge of the outer shell 6. Both of the shells 6 and 7 are preferably round in horizontal section. The inner shell of the pot 7 isV spaced from the bottom of the outer shell 6 and said outer shell is formed with depending leg-forming lflanges 10 and at. one side with a radially exftended cylindrical plug-holding seat 11.

On the bottom of the pot 7 preferably integral therewith, is 'a terminalblock seating flange 12, preferably of rectangular outline, so as to form a bearing surface for a rectangular terminal block 13 of insulating material, such as vulcanized Vwood libre, gutta percha or the like. This terminal block 13 is rigidly but detachably secured to obliquely opposite corners of the flange 12 by screws 14 and these same corners of said ange are shown as extended to form lugs-15 provided with internally threaded seats. By means of screws 16 l,passed through perforations in the bottom of the outer shell Gand screwed into the seats of the lugs 15, .the two shells 6 and 7 are rigidly connected and the flanged upper edge of the latter is tightly drawn onto the upper edge of the former. The bottom of the outer shell 6 is provided with a recess through which the terminal block 13 is freely passed so that the lower surface of said block is accessible when the two shells are rigidly connected.

The inner shell or pot 7 is provided with a detachable lid or cover 17 formed with a conical flange 18 that closely fitsthe lid seat 8 of the pot 7 and thereby tightly closes said pot against the escape of steam under aipressure less than that'required to lift the lid.

Applied directly around the pot is an electrical heater made up of a plurality of' coils having their terminals anchored to i' suitable binding posts applied 'on the terminal block 13. Instead of using a single coil for a heating element, I preferably employ a multiplicity of coils connected in parallel and thermostatically controlled on a plan disclosed and broadly claimed in my Vprior Patent #1,453,889,0f date May 1, 1923, and entitled Tire vulcanizer. 'Hence, for the purposes of this case, the wiring system disclosed, but which may be varied, is as fol# lows.

Mounted on and extended through the central portion of the terminal block 13 are terminal screws 19 and 20. VBy means of nuts 19 and 20 on the upper ends of the screws 19 and 20, thermostat bars 2l and 22, respectively, are secured. These thermostat bars 21 are oa well known laminated type,

which, under increasingtemperature,willv assume curved form,causing the ends to rise. Normally, or at "low temperatures, the ends of the bars 21 engage the points of Contact under low temperatures, engage with the points of contact screws 22l and 22 thatvalso extend through and have threaded engagement with the terminal block 13. Mounted on vand extended through therterminal block 13 is an additional terminal screw 23.Y From screws 21'? and 2lb, which, as shown, Vhave Y threaded engagement with andV extend through the terminal block 13. In asimilar manner, the ends of the `bar 22, normally or the terminal screws or contacts 21, 21, 22', 22h, and 20, wires 24, 25, 26, 27 and 28, re-

spectively, are extended and at their extend-Y ed ends, these several wires are, by n. eommon wire 29, connected to the screw 23. The

several Wi res 24, 25, 26, 27 and 28 are extended and wound around the pot 7 to form the heatingcoiL Preferably, the several wires, as

best shown in Fig. 2, are insulated. A compartment is formed at the bottom of the bowl bg' the flange 12 that is normally completely an tightly closed by the terminal block 13 and within this compartment the thermostat bars 21 and 22 are held' by said block Where they are protected from dirt and dust and also kept from the air to prevent rust' and corrosion. v Y v Seated in the plug seat 11 is a contact plug 30 having the customary extended contact prongs 31-and 32. By a wire 33, the contact prong 31 is connected to terminal screws 19 and 20, and by a wirev 34, the contact prong 32 is connected to the screw 23. The contact screws 21a, 2lb, 22a and 22b are so adjusted that the thermostat bars 21 will progressivelyD open and close the various branch circuits connected thereto,but an electrical circuit for low, temperatures will always be maintained through the wires 34, 29,- 28 and 33. 0f course, the current for supplying the heat willvbe applied by inserting a contact socket into the seatv 11 and .onto the contact prongs 31 and 32.

From what ghas been said, itwill be understood that so far as the present invention is concerned, the electrical heating element may y take various different forms.

It will be noted that the seating ange l2 forms a recess affording clearance for the upper ends of the terminal screws, the nuts applied thereto and the thermostat bars 2l and 22. The three mainelements 6, 7 and 17 of the heating utensil are preferably castings of suitable metal, such as iron or aluminum. The numeral 35 indicates insulating material placed within the outer shell 6 and surrounding the coils of the heating element.

The device so far described is complete, but

in the drawings, I- have illustrated a pan-- heating element may be made before the pot is inserted within the outer shell, and that, after the pot has been applied within the casing and secured by the lscrews 16, all that is necessary to complete vtheelect-rical connections is to connect the wires 33 and 34 to the vscrews 20` and 23. If the two shells of the heater are to vbe separated, it is only necessary to disconnect the two wires 33 and 34, and this beingdone, the pot may be removed without disturbing any of the electrical 'conneotions applied thereto.

What I claim is:

A heating utensil comprising an outer shell,

a bowl applied within the outer shell and having in its bottom a depending endless ter- -minal-bl'ock-seating iange and a compartment within said ange, said outer shell having in its bottom an aperture coincident with the compartment, a heating element for the bowl, an insulating termina-l block tittlng m said aperture, seated on said flange and detachably held thereon, said terminal block normally closing the aperture i n the outer shell and completely closing said compartment, and a thermostat in the electric circuit for the heating element mounted o n the terminal block and held thereby within said compartment. i

In testimony whereof I aiiix my signature.

EVEN J. RoHNE. 

